Biophysical Society Thematic Meeting | Singapore

Mechanobiology of Disease

Tuesday Speaker Abstracts

Effects of a Soft Massaging Device, Based on an Oscillating Torque, Upon the Expression of Some Dermal Proteins of Human Skin. Influence of Frequency. Elisa Caberlotto 1 , Zane Miller 2 , Aaron Poole 2 , Laetitia Ruiz 1 , Jean-Luc Gennisson 3 , Miguel Bernal 3 , Mickael Tanter 3 , Mickael Poletti 2 , Lauri Tadlock 2 . 1 L'Oréal, Paris, France, 2 L'Oréal, Redmond, WA, USA, 3 Institut Langevin, Paris, France. Different biological models have shown how mechanical stimulations may induce physiological response(s) from solicited cells, tissues or organs. In models of cultured skin cells, the frequency of the mechanical stress appears a paramount parameter, generating a biological response(s) of some cells, particularly from dermal fibroblasts. Our objective was to explore, in a full-tissue model (ex-vivo human skin explants) the effect(s) of mild massages provided by a torque test device able to generate cyclic strains at different frequencies (40 to 180Hz) and amplitudes (±3° or ±7°). In collaboration with the Langevin Institute, the propagation of mechanical waves generated by the massage device was initially analyzed using ultrafast ultrasound imaging in vitro (on an elastomer material mimicking skin) and in vivo for designing the best shape of the massaging device. Accordingly, three small teflon bulbs, disposed as summits of an equilateral triangle (2.6cm side) were found convenient. Skin explant samples, maintained in a survival biological state, were twice daily submitted to the massaging device for one minute, for 10 days, at different frequencies and amplitudes. At days 0, 5 and 10, samples were processed by immuno-histological procedures, allowing some structural dermal proteins to being semi-quantified (fluorescence). As compared to non-massaged skin explant samples, the massaging procedure clearly led some dermal proteins (Decorin, Fibrillin, Tropoelastin) to being over-expressed. Modulations of these expressions were found frequency-dependent, the highest at 75Hz frequency, for a ±3° amplitude. In conclusion, the ex-vivo human skin explant model used here describes, for the first time, the profound biological/structural effects induced onto the human skin by a superficial and defined oscillating strain. This model appears promising for studies that deal with the precise mechanisms of mechano-transduction.

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